Although pot is still illegal at the federal level, 28 states have now passed comprehensive medical marijuana laws, and eight of them, as well as the District of Columbia, have also legalized recreational use of the drug for adults ages 21 and older. Other states have decided to decriminalize cannabis—which means that people caught with small amounts of the drug likely won’t be prosecuted, particularly for a first offense.

So does this mean that HR professionals must change their workplace policies regarding marijuana? In a word, no—although the issue is worth revisiting periodically in light of frequent legislative changes, developments in drug testing and shifting attitudes toward pot.

“Employers need to know that, even with the proliferation of marijuana laws, it’s still perfectly OK to tell employees that they can’t use marijuana at work, can’t bring marijuana to work and can’t be impaired at work,” says Kathryn Russo, an attorney with Jackson Lewis in Long Island, N.Y.

Recreational Use

While HR professionals may be tempted to approach marijuana in the same way they do alcohol in states where recreational marijuana is legal—that is, to deem it unacceptable at work even though employees can partake in it legally off duty—this strategy gets complicated when employers engage in drug testing.

Because marijuana is metabolized differently than alcohol, it stays in people’s systems longer. So regardless of whether a test is done on blood, urine, saliva or hair, it can’t detect whether the drug was last used within the past several days or a couple of hours ago.

“An employee could smoke pot over the weekend while off duty and still test positive on Monday,” Russo explains.

However, testing technology is advancing rapidly, so it’s important to stay abreast of the latest developments. “Scientists are working hard, and we hope to be able to accurately test impairment very soon,” says Austin Smith, an attorney with Ogletree Deakins in Denver.

In the meantime, marijuana is still considered a Schedule I drug under the Controlled Substances Act—which means the federal government has identified it as having a high potential for abuse and no accepted medical purpose. Other such substances include heroin, LSD, ecstasy and peyote.

Medicinal Use

Medical marijuana presents greater challenges for employers than recreational consumption due to the confusing, and sometimes contradictory, matrix of laws that come into play.

Under many state laws, workers can be fired for a positive drug test even if they are permitted to use medicinal marijuana off duty. But employees may not know that they lack employment protections, says Danielle Urban, an attorney with Fisher Phillips in Denver. Medical marijuana cardholders often believe their company’s zero-tolerance policies don’t apply to them because they have a “prescription” from a doctor, according to Urban. Yet, in reality, physicians are not allowed to prescribe Schedule I drugs under federal law; they can only provide “recommendations” for patients’ use.

Further complicating the picture, some states prohibit discrimination against employees and job applicants based on their status as medical marijuana cardholders.

In New York, for example, certified medical marijuana users are considered individuals with disabilities under the state’s human rights law.

In such states, managers and HR professionals should engage in an interactive dialogue with the employee to search for a reasonable accommodation for medical marijuana cardholders, Russo suggests. Perhaps an alternative medication could be prescribed, for example.

Another option is to let the employee take leave while using medical marijuana, Urban says.

If the employer opts to accommodate medical marijuana use the first time the issue arises, its leaders will need to think carefully about how they will consistently address similar requests in the future.

Here, too, the legislative landscape may change. Activist groups such as the Marijuana Policy Project (MPP) are fighting to end prohibitions on marijuana through lobbying and state ballot initiatives. MPP “will continue to work for protections under state law for medical marijuana patients, as well as to change federal law so that marijuana is no longer excluded from [Americans with Disabilities Act] protections,” says the group’s communications manager, Morgan Fox.

So what should employers do in states that provide employment protections for medical marijuana users?

The answer depends on how much risk they are willing to assume, Russo says. Some business leaders may opt to maintain their zero-tolerance policies because marijuana remains illegal under federal law. From a legal perspective, this option is relatively safe, since employees who have challenged such policies in states with legalized medical marijuana have lost court cases due—at least in part—to the conflict with federal law.

But other employers might prefer to comply with state and local nondiscrimination provisions as best they can, particularly if a blanket no-tolerance policy doesn’t seem necessary for all segments of their workforce.

Indeed, as laws change and misinterpretations abound, business and HR leaders may want to consider whether immediate termination is always the best option when employees fail a drug test. One alternative is a so-called last-chance agreement, in which a worker with a positive result on a drug screen agrees to submit to repeat testing at some point over the next 18 months or so; if another assessment also turns out positive, he or she would be immediately terminated. However, HR professionals should review drug-testing laws in the states where they operate before creating a policy like this, since those laws vary from state to state. HR professionals may want to say to employees, “Here is a copy of our policy just in case you misunderstood how it works,” Urban says.

Moreover, it’s worth bearing in mind that testing is not the only way to gauge drug use. Some employers have moved away from screening altogether and instead opt to address impairment and performance issues in other ways. Supervisors can be trained to report reasonable suspicion based on behaviors, bloodshot eyes and other factors, for example.

At the end of the day, deciding what type of policy to adopt may depend on whether a business has a lot of positions with duties that are dangerous to perform if workers are impaired, Russo says. Companies may not want to tolerate any safety risk for forklift drivers, for example.

The Bottom Line

In this dynamic legislative climate, experts agree that clear communication of whatever approach a company takes is key. For employers that want to maintain a zero-tolerance policy, Urban says, it’s much better to step out ahead of any potential issues and say, “We understand that marijuana just became legal, but we still have a zero-tolerance policy and here’s what that means."

Lisa Nagele-Piazza, J.D., SHRM-SCP, is senior legal editor for SHRM.

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